Useful Tips

Garage foundation depth


Car owners take their garage construction issues seriously and often do this on their own. If the foundation of the future building is carried out taking into account building requirements, then the shrinkage of the structure will occur evenly, and cracks on the walls will not appear. Knowing how to properly pour the foundation under the garage, you can ensure the durability and reliability of the future building.

Performing the preparation of the foundation, filling the site under the car - affordable work, even for people who have not encountered construction. We will get acquainted with the features of these operations. Before the start of construction, determine the type of foundation, the characteristics of the fill, take into account the mass of the structure, the characteristics of the soil. There are no trifles in this matter, the size of the garage for the car and the height of the base are important. Everything must be foreseen in advance! With this approach, you predict future costs and avoid problems during the operation of the building, as well as during the construction process. Let us consider in detail the stages of work.

The foundation is the so-called "sole" of the building, it must have balance, stability and compensate for all power loads

Beginning of work

Before embarking on earthworks, perform a set of preliminary measures:

  • Development of a sketch of a future building, performed at the initial stage of work. When sketching, analyze the presence of communications under the construction object, the depth of the location. This will avoid conflicts with the owners of neighboring plots and utilities.
  • Calculation of the mass of the future garage, allowing you to determine the type of foundation. Using a preliminary drawing with dimensions, calculation results, the need for building materials is determined, the level of costs is estimated.
  • Site selection for construction. It is not enough just to determine the place of the structure, it is important to investigate the characteristics of the soil and start digging trenches after performing geological studies. Exploration of the soil will determine the level of groundwater, make a decision on the depth of the trench. Do-it-yourself foundation pouring under the garage is made after sampling at the construction site and analysis of samples. Remember that with increased soil moisture, drainage is necessary. After all, freezing water in the soil causes deformation of the base, and in the future can cause cracks.
  • Marking the site using rope and pegs. This is the final stage, allowing you to accurately fix the boundaries of the structure. The exact contour of the building will allow you to properly complete the preparation and concrete the area under the garage.

The next stage is earthwork: with the help of a peg and a rope, you need to make exact boundaries of future trenches, they will help to properly fill the garage foundation and not distort the “base”

Assessment of the influence of soil features

Before starting concrete work and digging trenches, analyze the type of soil on which the concrete platform for the room will be located. The type of soil determines the depth of the trench, which depends on the density of the soil. The recommendations are as follows:

  • Stony and rocky rocks, characterized by hardness, allow you to build a garage on a planned site, without preparing trenches.
  • Soils with gravel require the depth of the substrate above the freezing level.
  • The foundation on clay soil forces a trench to be filled with a depth below the freezing layers.
  • Sandy rocks, characterized by flowability, require foundations with a depth of more than 2 meters.
  • Peat bogs are unsuitable for construction, but they allow construction to be carried out after complete removal of peat and filling the cavity with a gravel-sand mixture.

When evaluating the ground, remember the main thing - the garage is installed on a solid foundation.


What to choose the basis for the construction of a garage? Before you pour the foundation under the garage with your own hands, you need to choose the right option. Consider the possible types of bases:

  • Tape, which is a concrete mortar poured into a wooden formwork. The base is traditionally used in normal soils, when the wooden frame is located along the perimeter of the structure in the prepared trench and is not recommended if groundwater is located close to the surface. The formwork can be dismantled or stationary.

Survey work determines the depth and method of filling the garage base, because groundwater can behave unpredictably

  • Floating (solid), which is a kind of tape designed for installation on unreliable soils. The base is a solid reinforced concrete slab, buried below the zero mark.
  • Solid, made in the form of a contour of reinforced concrete foundation slabs.
  • Concrete, flooded along the contour of the garage. It consists of rubble stone, cement mortar and is laid on a pillow of coarse sand.

It is important to ensure the convenience of entry into the room, try to avoid attracting heavy lifting equipment and wage workers. Meeting these requirements will significantly reduce costs.

Strip design

A monolithic strip base is a popular option for a garage with standard sizes. Owners of cars that prefer this basis are attracted by simplicity, reasonable price.

To properly fill the foundation under the garage, use a removable formwork

The sequence of measures for the construction of the strip foundation corresponds to the proven algorithm:

  • preparation of the trench in accordance with the markings made, providing a width of the base 20 cm wider than the walls,
  • laying filter sand and gravel mixture 15 cm thick, compulsory compaction,
  • installation, ensuring immobility, tightness of wooden formwork panels,
  • loop reinforcement with steel reinforcement with a diameter of at least 0.8 -1 cm,
  • mixing the working mixture
  • pouring into the concrete cavity to the required height,
  • leveling the upper plane with a trowel,
  • moisturizing (during hot weather) the surface during the first three days,
  • waterproofing surface protection with sheet roofing material.
  • The quality of the tape structure is ensured by the following recommendations:

    • Ensure the level of the trench under the foundation so that the depth is below the freezing point of the soil for a given area.
    • Seal the sand and gravel mixture before serving each new serving.
    • Check the straightness of the installation of the formwork around the perimeter of the structure.
    • Follow the recipe of the mixture, ensuring compliance with the brand M200 and above.
    • Portion filling the volume, do not allow breaks, evenly distribute the solution along the contour of the opening. This will avoid docking seams, ensure the integrity of the platform.
    • Remove air cavities using fittings or an internal vibrator.
    • Lay waterproofing layers with overlap to impede moisture at the joints.

    If you plan to fill the foundation yourself, then the garage plan, in which there is a standard design and a standard foundation depth, is best suited for this.

    Floating foundation

    Being a kind of tape-type base, the floating base compensates for soil vibrations, perceives loads and is not sensitive to natural whims. What is the design of such a foundation for a car? It is a recessed concrete slab reinforced with steel reinforcing mesh.

    When arranging a floating base, observe the sequence of work:

    • Dig a rectangular pit.
    • Cover the base with a sand pad, compact the surface.
    • Install mesh reinforcement cage for strength.
    • Fill the foundation with concrete mortar until it is completely immersed in the reinforcement.
    • Plan the surface.

    After hardening, you can install waterproofing, concrete the platform for the vehicle using cement-sand mortar.

    The use of reinforced blocks

    For a major garage, the construction of which is significant in weight, foundation blocks can be used as a foundation. Reinforced concrete slabs are placed in a pre-prepared trench with the help of lifting equipment. If necessary, the upper plane is reinforced and poured with concrete.

    Doing the installation of the foundation for the garage using concrete blocks, you can’t rely solely on your own strengths during the manufacture of laying and working material

    Such a platform is able to withstand the mass of a heavy structure, to ensure stability over a long period of operation.

    Concrete base

    The foundation of rubble stone fixed with concrete mortar is an inexpensive and one of the most common options. It is convenient if you do the foundation pouring under the garage with your own hands, in this case there is no need to use specialized construction equipment.

    The work is performed in the following order:

    • mark the site, dig a trench of the required size,
    • prepare Portland cement grade M400, rubble, crushed stone, sand,
    • pour gravel and sand composition to the bottom, compact,
    • knead the cement-sand mortar, adding 1 part cement and water to 2 parts of sand,
    • lay one layer of rubble stone on the bottom, tamp and pour the solution on top,
    • sequentially laying and pouring layers, fill the volume until the final layer of cement reaches the required level.

    Arrangement of a platform for a car

    If the foundation is completely filled under the garage with your own hands, proceed with the preparation of the site for the vehicle. At first glance, it seems that this is a simple job, especially if the contour of the site is limited by a previously prepared foundation. However, there are some features that you need to know in order to ensure surface durability, to prevent cracking.

    Prepare the base for the machine in the following sequence:

    • Plan the site located inside the foundation edging. Eliminate surface irregularities that increase the consumption of concrete mixture and violate the uniformity of the structure.
    • Lay a pillow of crushed stone and sand mixture 20-40 cm thick on the bottom, carefully tamp. Moisten the surface and ensure its flatness using available means.
    • Cover the surface with agrofiber, which will hold the cushion material and let moisture pass freely.
    • Install the beacons, observing the distance between them of 0.5 meters. They, according to technology, are required to ensure the flatness of the concreted horizontal surface. Use a standard drywall profile. Ensure its immobility by fixing the cement-sand mortar lined with slides. Use a level to control horizontality.

    If you want to build a garage, then first of all you need to take care of arranging and installing the optimal supporting structure

    Construction material

    Today, there are a large number of building materials from which you can build a garage. But the most optimal has always been and remains a brick, which can withstand the load for many years and not wear out.

    Foundations come in many forms:

    This is a solid array of slabs under the entire building and is the strongest view.

    It looks like tightly clogged piles into the soil. Such a foundation is suitable for any soil and therefore is a universal type.

    Garage foundation strip ”w>

    It is a formworkin which concrete mixture is poured around the perimeter.

    For each building with its own area and load, for a particular type of soil, a certain type should be chosen. You need to know that the strength and reliability of the foundation will directly depend on its depth.

    For clay soils, it is preferable to choose a welded type of foundation, the tile type will be considered quite acceptable, and for sandy soil it is best to choose a strip foundation.

    How to calculate?

    The garage is quite an important building and therefore it is worth paying special attention to the calculations of the foundation. The garage must protect the car from the adverse effects of climatic conditions.

    The strip type of foundation is carried out at a depth of up to 1.7 m, there is simply no reason to do it deeper.

    At the moment, the best option for the middle strip is a combination of strip and slab foundations.

    You can calculate the prices, for example, if the garage is 6 by 8 meters:

    1. Earthwork: 24m3 × 700 rubles. = 16 800 rub.
    2. Sand pillow 10m3 × 500 rubles. = 5,000 rub.
    3. Concrete on a tape 4m3 × 5,000 rubles. = 20 000 rub.
    4. Sand filling 10m3 × 500 rub. = 5,000 rub.
    5. Concrete under the slab 5m3 × 5000 rubles. = 25 000 rub.
    6. Armature A-III 12 mm 1200mx26 rub. = 31,200 rubles.

    Total materials obtained at 103,000 rubles. If you pay for work, then you need to add another 80%.

    Construction stages

    1. Initially, think over and calculate which pit is needed, it will be most optimal to dig it at a depth of 50 cm. Next, the foundation is covered with sand with pouring and tamping of 20 cm.
    2. A tape of 30 × 40 cm is made around the perimeter. Reinforcement horizontal: 3 rods of A-III reinforcement in 2 rows, vertical - release through 40 cm high above the foundation 300 mm (for bundles). It is necessary to calculate the materials for formwork and reinforcement.
    3. Further, sand is poured inside under the tamper with spilled water, sand is covered with a polyethylene film (so that the cement milk does not go into the sand and the concrete does not lose its strength). Knitted frame in 2 layers of reinforcement A-III with a mesh of 200 × 200 mm. The thickness of the plate can be made 10 cm.

    The depth of the foundation for the garage will directly depend on the height of the freezing ground and the flow of groundwater. If the depth of freezing is not great, but groundwater passes low, then the foundation can be laid out with a depth of 0.4 meters and add to this figure the size of the sand cushion and a layer of gravel.

    This kind of foundation would be an ideal choice for building on sandy soil, which is almost impervious to freezing.

    The foundation on clay and marshy soils is best deepened by 1.5 meters. Thus, erosion and uncleaning of the soil will not take place, which will prevent the destruction of the foundation.

    The depth of the foundation should always be greater than the amount of soil freezing, at least 0.2 -0.3 m.

    The thickness of the walls of the garage will directly affect the width of the foundation for the be completed is approximately 30% more.

    This applies to any type of foundation, and even to slabs connecting the foundation piles.

    So, for example, the width of the walls will be 12 cm, this size has a standard brick (if the masonry is one brick), then the thickness of the walls of the wooden formwork will be 2.5 cm. And in this case, the width of the foundation under construction will be 20.6 cm.

    Bookmark Nuances

    If you do not plan to put more than two cars in the garage, you should not build a large garage, and therefore you will not need a powerful, strong foundation. In the case of one manna, you can completely get by with a light, modest base.


    1. Before starting construction, it is recommended to determine which communications pass through the selected place of construction so that they are not affected during the process. Thus, there will be no problems with neighbors and utilities.
    2. Further, it is worth at least sketching a sketch of what will be built later, a small sketch of the site along which you will need to navigate during the construction process.
    3. It is important enough in time to carry out the insulation of the lateral outer walls of the foundations with foam, which protects the earth from thawing and thereby prevents frost heaving of soils.
    4. A massive foundation is necessary if the garage will be built of strong bricks, 1.5 masonry or foam blocks. But there is one prerequisite for all types of construction - the foundation should be 20-30 cm higher from the ground, this will prevent the appearance of moisture and dampness in the garage.

    Why do we need a foundation?

    1. The foundation evenly distributes the load from the building to the ground.
    2. Protects the basement from moisture.
    3. Thanks to the foundation, the basement is naturally ventilated.
    4. Any soil moves with different intensities. A good foundation will protect the structure from damage caused by this factor.

    Design and dimensioning

    In order to properly make the foundation, it must first be designed and carried out certain calculations on the distribution of load on the ground where the structure will stand. This stage must be approached responsibly and with all severity. Otherwise, it may begin to deform and this will lead to additional financial investments for its repair at least and the destruction of the building as a maximum. For the proper construction of the foundation you need to go through the following rules:

    Garage foundation design

    • Find out at what level groundwater flows. The foundation must abut against the ground, and water should not make it float.
    • Examine the soil structure on which the garage will be built.
    • Make drawings indicating all dimensions of the foundation and construction.
    • Заранее приобретите все необходимые материалы и инструменты, хорошо продумайте, из какого именно сырья будет сделана основа.
    • When you conduct the calculations, take into account the mass of the foundation and its design features.
    • Calculate the technical parameters of the fundamental parts, for example, the diameter of the reinforcing bars and the distance at which they will be located, at what depth the foundation will be located and what will be its thickness, etc. All these actions will greatly simplify your further work.
    • Do not forget about waterproofing, which significantly increases the life of the base.
    • The depth of freezing of the soil should also be taken into account. The foundation must be deepened below this level.

    The garage building can be built right next to the apartment building. This will significantly save finances on the purchase of materials. In this case, one important rule must be observed. In no case do not connect the foundation of the house and the garage. Their shrinkage cannot be uniform. A heavier residential building shrinks harder and pulls the garage along, which can lead to its destruction.

    An ideal soil is one that does not swell, does not shrink, does not creep, has high strength and does not sag. But in practice, it is almost impossible to meet such a ground. Therefore, the builders came up with a little trick to make the foundation more reliable. A well-packed cave-gravel pillow helps to cope with all these soil deficiencies.

    To make the building durable and stable, try not to make mistakes in the calculations.

    Table: soil types

    Light soilDusty and fine sandy soil, loam and sandy loam. Move apart and change their location under heavy loads. Such soil must be additionally compacted. This is done in the excavated recess under the base using vibrating plates or a good ramming. On this basis, you can build any foundation.
    Medium and gravelly soilNot so heavy structures are built on such soil. They do not need to be additionally rammed. Suitable for the construction of any type of foundation.
    Clastic and rocky soilRelate to the most durable soils. Do not shift, do not erode, do not undergo heaving from low temperatures. The good bearing capacity of these soils is able to withstand heavy structures.
    Clay soilThis type of soil is one of the most problematic for construction. The main drawback is heaving. This is because the moisture entering this soil practically remains in it. With the onset of frost, the water turns into ice and expands. This puts pressure on the foundation, and with great force. Its deformations are inevitable. To reduce pressure, you can lay the foundation below the freezing level. But this does not completely eliminate the problem. Of course, there are still options for warming and building a drainage system. But all this greatly complicates the work.

    Any soil can always be replaced with a more suitable one. This is done by digging a large pit that exceeds the size of the foundation and replacing the existing soil with a more convenient one.

    Pushing the foundation out of the ground

    How to calculate the depth and width of the foundation

    Most garages have a small foundation. If you are not going to make it two-story, then additional strengthening of the base is not required. As much as possible, it should go one meter into the soil. This is quite enough. The classic width of the base is 400-600 millimeters. If materials such as a sandwich panel, metal profile or corrugated board will be used for the construction of walls, then this width can be left. If the walls are made of timber, gas or foam blocks, then the width of the foundation is added to the size of the selected material.

    Heavy materials like brick, cinder block, concrete and reinforced concrete slabs provide for the extension of the foundation, then 1,500 centimeters for reliability.

    If the groundwater level is high, then it is worth considering a shallow version of the base. And therefore, the material of the construction of walls should not be heavy so that the base can withstand it.

    Choosing the type of foundation

    A properly selected and high-quality implemented base for a garage is the key to the durability of the structure under construction.

    To determine the type of foundation for the garage, you should take into account all the circumstances of the real conditions of construction:

    1. Characteristics of the soil and the depth of groundwater.
      These indicators are determined by sampling during exploratory drilling. And even if the developer will have to incur certain costs to invite people to carry out such manipulations and conduct laboratory tests, it is still worth it. After all, having determined these parameters, you can choose the type of foundation for development, which will be most suitable for specific operating conditions.
    2. Estimated parameters and construction of the structure under construction.
      It is necessary to decide whether there is a need for equipping the garage with a viewing hole or a basement.
    3. Materials for construction.
      Be that as it may, all construction consumables are of different quality, which requires a special approach when using them: somewhere you need to add more water to mix the mortar, and somewhere you need to choose the appropriate fasteners to fix this or that facing material.

    Preparation of necessary tools and materials

    Most often, the foundation is made of precast or monolithic concrete, rubble stone or brick. Less often it is erected from wooden piles. The choice of material depends on the mass of the structure and soil properties.

    Hand drill, which is convenient to make pits under the pillars of the foundation

    Important! The use of red and silicate bricks for the construction of the foundation is not recommended, since moisture affects them destructively.

    Use frost and weather resistant materials for equipping the basement. This layer should be carefully waterproofed to avoid additional financial costs for a possible repair. The amount of material depends on the size of the base and its type. Therefore, it is necessary to accurately calculate it directly to each individual. The same goes for the tool list. For each type of material he has his own.

    The effect of soils on the choice of foundation type

    Fine sandy, dusty soil, loam and sandy loam - all these are weak soils. They tend to move and diverge under the influence of heavy loads from higher objects.

    Sandy soil, consisting predominantly of dust particles, fine or powdery loams, sandy loam, on which the construction of structures is planned, require careful compaction. This approach provides a more reliable fixation of the foundation on the land.

    Loam, sandy loam and other soft soils are compacted during tamping. Depending on the width and the required shrinkage size during soil compaction, smooth or cam rollers, pneumatic or diesel rammers can be used.

    Mostly weak soils, with the exception of thixotropic soils, do not retain moisture, therefore, after tamping, it is possible to erect support foundations of any complexity and configuration on this land plot.

    Medium and gravelly sandy soil can withstand even very massive foundations along with the structures standing on them. They do not require additional sealing, and are suitable for any construction work.

    Clastic and pitched soil is the most durable type of soil. They are not prone to displacement, erosion and are not subject to frost heaving. As a rule, high and heavy buildings are required on such soil, requiring a solid foundation.

    Clay soil is considered the most problematic in terms of construction work. One of the main disadvantages of such a soil is its heaving. Moisture that enters the soil does not seep into the underground layers of the earth, which leads to its accumulation in the outer layers of clay soil.

    When frost occurs, the water in the soil freezes and, according to its physical properties, the water that has transformed into ice expands.

    Due to this, the volume of soil increases, which leads to pressure on the foundation. It should be said that the forces exerting pressure on the supporting plane are quite large - about 5 tons per cubic meter, which can provoke its cracking and, as a result, displacement and even destruction of the structure itself.

    In order to limit the pressure of the soil on the concrete base, it is recommended to lay it below the level of soil freezing. This will help reduce the pressure on the foundation, but will not completely exclude it, which must be taken into account during the design of the building.

    Another option to eliminate soil pressure on the foundation will be its insulation around the entire perimeter. Of course, this is a rather time-consuming and costly option, but if you take into account what may be the loss from cracking the foundation, then it is likely the costs will be justified.

    There is another option to eliminate the problem with ground pressure on the support - water drainage. In this case, a special drainage system is used, located parallel to all sides of the supporting structure.

    Around a radius of 50 cm, a drainage ditch digs to the depth of the entire foundation. The perforated pipe is wrapped with filter material and lowered to a bottom of the ditch under a slight slope.

    In this case, a pit breaks out, exceeding the dimensions of the future building in size, and is filled with soil that is most suitable for construction. It is important to ensure that the soil that is backfilled is carefully packed.

    What types of base are - what to choose

    The most common option is tape. On it you can erect heavy buildings of brick and concrete. The columnar foundation is also popular. He perfectly holds wooden and frame buildings.

    It has such a name because of its appearance. It can be concrete, rubble, but concrete and brick. Depending on what it is made of.

    The cheapest option, almost free, is rubble. Despite the complexity of installation, it is popular because the materials for it can be found nearby and for nothing. They do not have to be bought. This option is distinguished by its reliability, durability, is not afraid of cold and moisture.

    The concrete version is a mixture of buta, gravel and gravel. This is an average cost type of foundation. It can be poured into the trench without first installing the formwork. This saves some of the money.

    A concrete foundation is a cement mortar in which you do not need to add additional elements for greater strength and durability. He is good without them. Compared to other types, this one is quite expensive, because it requires a lot of consumables.

    Brick option is used infrequently. It is not durable, especially if it is baked clay bricks or silicate.

    Garage design features

    How to make a foundation for a garage?

    When designing a garage, the future developer, who in this case is a motorist, must take into account such aspects of this issue:

    • the need for a viewing pit or basement,
    • the need for an extension or a second floor,
    • feature of building materials that will be used in the construction of the facility.

    If it is planned to equip a viewing hole in the garage, then for it it is necessary, before pouring the foundation, to prepare a trench. After this, the walls of the pit are sheathed with temporary formwork and only after that can you start digging a trench for the foundation.

    In addition, the need for laying wall drainage at a level below the surface of the supporting plane must be taken into account.

    The main condition for equipping the garage with a viewing hole or basement is the location of groundwater below 2.5 m, provided that this is the maximum height of their rise during heavy rainfall or snow.

    If this condition is not fulfilled, it is necessary to arrange a plastic drainage system under the pit / basement. But it’s worthwhile to understand that these manipulations will lead to a significant increase in construction costs.

    And it is logical that with an increase in the load during the construction of high-rise buildings of brick or concrete, the width of the support tape should be increased. According to generally accepted standards, the width of wall ceilings should be 12-15 cm less than the width of the foundation.

    How to pour and how much to dry

    1. Decide on the dimensions of the fundamental part of the structure. The average depth of the trench beneath it is 0.7–1 meters, and the width is about half a meter. The latter depends on the material of the walls.
    2. Then you need to mark the territory with pegs and a rope and dig a trench along the markings.

    Strip foundation solidifies in formwork

    Some professionals advise pouring concrete in several stages of 200-300 millimeters of concrete mix. Each subsequent layer begins to fill after a slight drying of the previous layer.

    Types of foundations

    There are several types of foundations for the construction of garages:

    1. Tape.
      The most common type of concrete support base, which is suitable for almost all types of soil, regardless of the structure and purpose of the structure under construction.
    2. Pile on hollow submersible piles.
      Hollow pipes with a diameter of up to 40 cm are installed around the perimeter of the future garage, reinforcing meshes are placed in them, after which they are filled with concrete mortar. The upper edges of the pile structure are aligned horizontally according to the stretched level. As a rule, such supporting foundations are used for the construction of structures on land plots with a natural slope. In addition, pile foundations stand well on soft soils.
    3. Pile on screw metal piles.
      In this case, a Mauerlat is used as the basis, which is fixed on the upper edges of the support. The main advantage of such supporting foundations is the complete lack of land work.
    4. Columnar.
      It is built on concrete pits and is used for almost any building.

    Also, as a basis for a garage, a block of concrete panels and a thickened strip foundation, erected on a wooden formwork, can be used. Be that as it may, the form of this structural element is selected depending on the requirements described above.

    The construction of the foundation for the garage: the main aspects of the issue

    As mentioned earlier, the durability of the structure under construction depends on a correctly selected and high-quality foundation for the garage. For lack of a building education, when designing a garage space for car storage, it is best to resort to the help of qualified specialists.

    Today, there are a lot of various offices and organizations that provide diverse services in the field of construction: from the development of an individual construction project to the organization of the entire construction process.

    Of course, this is an extra expense item, but at the same time, it will more than pay off than in the case of a self-constructed garage in the wrong place. Not to mention the subtleties of the design of such a room, where ventilation and ventilation of the room play a significant role.

    Read on how to properly build the foundation for a garage on your own.

    Description of step-by-step operations

    1. As in the case of the tape base, you first need to make markings and dig a trench.
    2. Then spreads a cave-rubble pillow, which must be tamped.
    3. In a ratio of 1: 2: 1, cement, sand and water are mixed, respectively. Use a bucket as one piece.
    4. Lay the rubble stone at the bottom of the trench in one row. Pour it with sand-cement mortar so as to cover the stones. Then again lay a row of stones. And again fill them with a solution. Continue until you fill the entire trench.


    It is used for lightweight structures, because it does not withstand heavy loads. It features a simpler installation method. Today, asbestos pipes are often used as pillars, where concrete is poured. It happens that the tree is also used as pillars. This is a pile option. Larch can withstand the weight of the structure and is quite durable. But this option is uneconomical, because the tree will cost a pretty penny.

    Garage column foundation

    Preparatory stage

    So, regardless of the manufacturing technology of the support base, before proceeding with the construction, it is necessary to carry out a number of preparatory work, which are as follows:

    • study of the site to determine the hydrogeological conditions in the place of the proposed construction,
    • choosing the right type of foundation support,
    • design of a garage taking into account design features,
    • calculation and purchase of all necessary consumables,
    • calculation of the area of ​​the proposed foundation, removal of the soil layer not only in the place of the foundation, but also on its borders, at a distance of at least 10-15 cm around the entire perimeter,
    • marking and digging trenches, for which pegs, shoelaces can be used.

    After all these issues are resolved, you can begin to fill the foundation under the garage.

    How to layout and build

    Such a base would be ideal for places where groundwater flows close to the surface. Его можно устанавливать на глубину до 350 сантиметров и больше. Существенным минусом такого варианта является невозможность сооружения подвала под гаражом.

    Угловые столбы устанавливаются глубже промежуточных на 50–100 сантиметров. Промежуточные ставят с шагом в 150–200 сантиметров.

    In order to put the pillars, it is necessary to prepare pits for them in advance. It is most convenient to use a drill for this.

    There are 2 ways to install reinforced concrete pillars. The first reinforcement is placed in a pit and poured with concrete mixture. The second is more complex, but has improved load-bearing capabilities. For him, roofing material spreads to the bottom, on which a pipe or wooden formwork is installed. Reinforcing bars are laid inside and everything is poured with concrete mortar made of cement of at least M300 or M400. Separately, make a base plate of at least 100 millimeters. Then it is concreted to the pillars.

    This is the most expensive option for a garage base. It is a kind of strip base and looks like a recessed reinforced concrete slab. But if the construction will take place where there are heaving and subsidence soils, then it will become ideal and will justify its price with quality. In fact, it is one solid slab that evens out the mobility of the soil. That is why it is also called a “floating” foundation.

    Scheme of the slab base of the garage

    A “floating” base is made using cement, reinforcement and roofing material. It can be ordinary, lattice monolithic or prefabricated and monolithic reinforced at the edges. Normal is the most economical option.

    Action algorithm

    Upon completion of the marking work, we begin digging a trench. It should be the depth corresponding to the selected type of foundation. But, as a rule, under the garage there will be enough trench depth from 50 to 100 cm.

    Further, the trench is covered with dry mixtures: first there is a layer of crushed stone or fine gravel - its thickness should be 20-30 cm. After careful leveling and tamping, river, quartz sand is poured over the first layer. For such purposes, sea sand is not very suitable.

    The thickness of this layer should be between 15-20 cm. Sand is also compacted, which is easiest to do by watering it and leveling it.

    How to do it yourself

    1. Dig a pit of the required depth, which depends on the nature of the soil.
    2. Put a sand cushion and tamp it well. Ideally, do this in several layers, each of which is individually wetted with water and rammed.
    3. Lay the reinforcement mesh to strengthen the structure.
    4. Now you can pour concrete mortar.
    5. After drying the solution, you can proceed to the construction of the floor screed.

    The most important thing in the construction of the foundation is not to forget about the inspection hole, if it is planned. Indeed, in a slab base, it will then be difficult to build it. It is better in such an option to provide a combined or strip foundation.

    Formwork device

    For the manufacture of this structural element, such consumables are suitable:

    • planed edged board,
    • waterproof plywood, not less than 1.2 cm thick,
    • chipboard,
    • Metal sheet,
    • cement particle board.

    You can pick up something else. The main thing is that it has a smooth forming surface.

    Before installing the formwork, the foundation pit must be waterproofed. For these purposes, a ruberoid laid in 2 layers is suitable. Also at this stage it is necessary to provide an entrance for communications, if any, in the garage. At the entrance place we place a plastic or asbestos-cement pipe.

    The formwork is mounted as follows:

    1. According to the pre-made marking, using lacing or pegs, we dig in racks from a bar with a cross section of 50 mm. The distance between them should correspond to the size of the plate material or pre-hammered board boards.
    2. Panels or panels are fixed to the support posts by means of screws on the inside.
    3. The width of the formwork is further enhanced by the jibs, due to which the structure is supported in the ground.

    Foundation reinforcement

    The algorithm of the reinforcing mesh device is as follows:

    1. The first reinforcing layer is formed at a distance of 5 cm from the waterproofing.
      At this stage, brick debris is typically used. The gap between the rods should be about 12-14 cm. They are fastened together by means of a knitting wire made of low carbon steel.
    2. The second step will be the installation of racks, which use chopped fittings.
    3. The second and subsequent reinforcing layers should be formed with a gap of 14-15 cm from the first, maintaining the same dimensions.
      The output of reinforcing elements beyond the concrete base is not permissible. This will provoke the development of corrosion on the foundation elements and to its partial, and then complete destruction.

    Concreting base

    The final stage of the foundation for the garage is concreting. The foundation is poured with a mortar based on concrete grade 300.

    The principle of its preparation is as follows:

    • cement grade M400 - 1 part,
    • middle-fine sand - 4 parts,
    • medium fractional gravel - 4 parts.

    The volume of water depends on the quality and characteristics of the above consumables. On average, about 4-5 buckets of water will be required for this set of loose mixture.

    Care must be taken during the manufacture of the grout. All dry materials are pre-mixed until completely dissolved in each other, and only after that water is gradually introduced in small parts.

    It is also worth noting that for the preparation of concrete it is better to use purified water without organic impurities or inclusions in the form of water plants and other vegetation.

    After preparing the solution, we proceed to pouring the foundation. This process is performed in layers. Each layer is carefully tamped and seated. This approach will relieve the supporting base from bubbles that adversely affect the quality of the foundation.

    Concrete dries for at least a week, and its full hardening occurs somewhere after 28-30 days. It all depends on the climatic conditions under which the construction work was carried out.

    During the drying of the concrete base, it must be covered with plastic wrap, and during hot weather, the foundation should be moistened several times a day with water, which will eliminate its subsequent cracking.

    It remains only to dismantle the formwork and carry out waterproofing work. Most often, bituminous mastic is used for this, under which the surface must be prepared by treating it with a primer.

    After applying bitumen mastic, we give the foundation to stand for 20-24 hours, after which the mastic is applied in a second layer. And only after a day can you organize backfilling and waterproofing of the concrete base with roofing material and gravel / gravel.

    Summarizing all of the above, I would like to add the following:

    1. The most important thing
      - it’s right to choose the type of foundation, because the durability of the building being built on it depends on it.
    2. Consumables
      - Another important condition for the construction of a quality foundation for the construction. It is better to give priority to consumables of well-known manufacturers.
    3. Compliance with phased production.
      Adhering to the algorithm of the foundation foundation device, a person, even without a building education and some special skills, can independently realize his task.